Device and method for diagnosing abnormalities in power supply equipment.

Abstract

To provide an abnormality diagnostic device of a power plant which can be easily attached / detached and accurately diagnose the presence / absence of occurrence of an abnormality in a power plant in a short measurement time and an abnormality diagnostic method using the abnormality diagnostic device.SOLUTION: An abnormality diagnostic device diagnoses an abnormality in a power plant which includes a housing and a conductor that is fixed to the housing at a prescribed fixation spot and supplies a current to a load. The abnormality diagnostic device includes an excitation unit and a measurement unit. The excitation unit applies vibration to the conductor. The measurement unit measures a value indicating the characteristics of the vibration applied to the conductor by the excitation unit. The excitation unit and the measurement unit are arranged at the fixation spot or in the vicinity of the fixation spot.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] Embodiments of the present invention relate to an abnormality diagnosis device and an abnormality diagnosis method for power supply equipment.

Background Art

[0002] In power supply equipment such as substation equipment, preventive maintenance is carried out through regular maintenance inspections and condition monitoring to ensure a stable power supply. Due to initial defects, aging deterioration, dirt, etc., power supply equipment may locally overheat. Depending on the degree, the overheated part may be damaged by burning. In particular, the part where conductors are fastened by fastening members such as bolts may overheat due to an increase in contact resistance between the conductors caused by loosening of the fastening members.

[0003] Such loosening of the fastening member can be detected by capturing changes in the mechanical vibration characteristics of the fastening location. According to such a method, it is possible to detect contact failure due to loosening of the fastening location before overheating of the fastening location becomes apparent, and diagnose abnormalities in the power supply equipment. On the other hand, in order to determine whether the fastening state of the fastening location is normal, it is necessary to determine the difference in vibration characteristics from a normal fastening state without loosening. Therefore, it is required to measure the current fastening state of the fastening location after obtaining in advance the vibration characteristics of the fastening location in a normal fastening state, that is, the normal value. These measurements need to be carried out within a limited time, such as during the on-site adjustment period after installation for a new facility, or during the downtime for regular inspections for an existing facility.

[0004] Also, inside the panel of the power supply equipment, there are circuit breakers, transformers, branch buses, power cables, etc., and there is a limit to the space for installing necessary devices such as vibrators and vibration detectors, and it may be difficult to install the necessary devices.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] Therefore, we provide a power supply equipment abnormality diagnosis device that is easy to attach and detach and can accurately diagnose the presence or absence of abnormalities in power supply equipment in a short measurement time, and an abnormality diagnosis method using the abnormality diagnosis device. [Means for solving the problem]

[0007] The abnormality diagnosis device of the embodiment diagnoses abnormalities in a power supply system comprising a housing and a conductor fixed to the housing at predetermined fixed locations and supplying current to a load. The abnormality diagnosis device comprises an excitation unit and a measurement unit. The excitation unit applies vibration to the conductor. The measurement unit measures a value indicating the characteristics of the vibration applied to the conductor by the excitation unit. The power supply equipment is configured such that each of the plurality of conductors has a fixed point, and adjacent conductors are electrically connected at fastening points where they are fastened with a first fastening member. Each of the plurality of conductors is fastened to the housing at the fixed point with a second fastening member. The vibration unit is positioned near the second fastening member that fastens one of the conductors fastened at the fastening point. Multiple measurement units are positioned near the second fastening member or the second fastening member. One of the multiple measurement units is positioned near the same second fastening member as the vibration unit. The other measurement units are positioned at different locations near the second fastening member that fastens a conductor located on the opposite side of the fastening point from the one conductor, or near the second fastening member. The vibration unit and the measurement units positioned near the same second fastening member as the vibration unit are configured as a single integrated component. [Brief explanation of the drawing]

[0008] [Figure 1] A block diagram showing a schematic configuration of the abnormality diagnosis device according to the first embodiment. [Figure 2] A schematic diagram showing the configuration of an abnormality diagnosis device used to diagnose abnormalities in power supply equipment according to the first embodiment. [Figure 3] A diagram showing the time transition of the acceleration of vibration generated by the excitation unit during normal and abnormal conditions in the abnormality diagnosis device according to the first embodiment. [Figure 4] A block diagram showing a schematic configuration of the abnormality diagnosis device according to the second embodiment. [Figure 5] A diagram schematically showing the configuration of an abnormality diagnosis device used when diagnosing abnormalities in power supply equipment according to the second embodiment. [Figure 6] A schematic diagram showing a general configuration example of the vibration measurement unit according to the second embodiment. [Figure 7]A schematic diagram showing a general configuration example of a modified vibration measurement unit according to the second embodiment. [Modes for carrying out the invention]

[0009] The following describes the abnormality diagnosis device and abnormality diagnosis method for power supply equipment according to the embodiment, with reference to Figures 1 to 7. The power supply equipment comprises at least one panel. Each panel is configured with circuit breakers, disconnectors, current transformers, transformers, conductors, etc., arranged in a space separated from the outside by a housing. When an abnormality occurs, the power supply equipment activates circuit breakers, etc., to cut off the power supply, for example, to protect the circuits in the power transmission and distribution system, control the power, and monitor the equipment. The power supply equipment supplies power to the load via conductors. The load to which power is supplied is, for example, factory equipment or building equipment.

[0010] (First embodiment) Figure 1 is a block diagram showing the schematic configuration of the abnormality diagnosis device 1 according to this embodiment. As shown in Figure 1, the abnormality diagnosis device 1 comprises, as its main elements, an excitation unit 2, a measurement unit 3, a communication unit 4, an output unit 5, and a control unit 6. The abnormality diagnosis device 1 diagnoses whether or not an abnormality has occurred at the point of diagnosis of the power supply equipment. The point of diagnosis is, for example, a fastening point where conductors are fastened together with bolts (hereinafter referred to as a bolt fastening point). The abnormality diagnosis device 1 diagnoses whether or not the bolts in the bolt fastening point are loose.

[0011] The vibration excitation unit 2 applies vibration to the conductors of the power supply equipment. The configuration of the vibration excitation unit 2 is not particularly limited as long as it is capable of applying vibration to such conductors. In this embodiment, as an example, a means for automatically generating vibration, such as an exciter equipped with an electric actuator, is applied to the vibration excitation unit 2. However, the vibration excitation unit 2 may also be a means for generating vibration manually, such as a hammer.

[0012] The measurement unit 3 measures values ​​that indicate the characteristics of the vibration applied by the excitation unit 2. The vibration characteristics are the characteristics of how the vibration applied by the excitation unit 2 is transmitted, and include, for example, the acceleration, velocity, amplitude, frequency, and displacement of the vibration. In this embodiment, as an example, a contact-type acceleration sensor such as a piezoelectric element or a strain gauge is applied to the measurement unit 3. Therefore, the measurement unit 3 measures the value of the acceleration of the vibration applied by the excitation unit 2 as a value indicating the vibration characteristics. However, the measurement unit 3 may also be a non-contact type displacement sensor that measures capacitance or eddy currents.

[0013] The communication unit 4 is, for example, a communication control device or communication module for enabling communication with external communication devices via a communication network. The communication unit 4 communicates with external communication devices via wired or wireless means and transmits and receives data.

[0014] Output unit 5 outputs diagnostic information regarding the presence or absence of abnormalities in the power supply equipment, specifically the diagnostic status and results, such as whether or not the bolts fastened between conductors are loose. Output unit 5 can be, for example, an indicator light, a monitor, a panel, a speaker, or a combination thereof. By doing so, output unit 5 can illuminate (flash) an indicator light, sound notification or warning sounds, play or display notification or warning messages, etc., to ensure that users are fully informed of the diagnostic results and to raise awareness. Users are, for example, workers who install, maintain, or inspect power supply equipment.

[0015] The control unit 6 includes a CPU, a storage device (non-volatile memory), a memory, an input / output circuit, a timer, etc., controls the operations of the vibration unit 2, the measurement unit 3, the communication unit 4, and the output unit 5, and executes an abnormality diagnosis process in the abnormality diagnosis device 1. The control unit 6 is configured as an information processing device such as a personal computer, a smartphone, a tablet terminal, a server, etc. The control unit 6 is connected to the vibration unit 2, the measurement unit 3, the communication unit 4, and the output unit 5 by wire or wirelessly. The storage device of the control unit 6 appropriately stores programs and various types of information (data) necessary for the processes performed by the vibration unit 2, the measurement unit 3, the communication unit 4, and the output unit 5. For example, the storage device stores the measured value of the vibration acceleration indicating the characteristics of the vibration of the conductor generated by the vibration given by the vibration unit 2 in a state where the bolt is fastened with an appropriate tightening torque in the bolt fastening part, that is, the normal value. Such a normal value is read into the memory as a parameter when diagnosing an abnormality of the power supply equipment described later.

[0016] The control unit 6 performs startup, stop, operation control, etc. of the abnormality diagnosis device 1. Therefore, the control unit 6 executes the programs and firmware read into the memory, and acquires various types of information (data) necessary for these executions from the vibration unit 2, the measurement unit 3, the communication unit 4, and the output unit 5. By executing a predetermined arithmetic process (abnormality diagnosis process) according to the acquired information, the control unit 6 diagnoses the presence or absence of an abnormality in the power supply equipment, specifically, the presence or absence of loosening of the bolt in the bolt fastening part between the conductors.

[0017] The control unit 6 has a diagnosis information generation unit 61 and a diagnosis unit 62. The diagnosis information generation unit 61 and the diagnosis unit 62 are stored in the storage device as programs, for example, and are read from the storage device into the memory and executed.

[0018] The diagnosis information generation unit 61 generates diagnosis information based on the vibration characteristics measured by the measurement unit 3, that is, the measured value of the vibration acceleration indicating the characteristics of the vibration generated in the conductor by the vibration given by the vibration unit 2. The diagnosis information generation unit 61 calculates a decay rate (decay ratio) according to, for example, the vibration acceleration measured near the vibration unit 2 and at another location away from the vicinity.

[0019] The diagnostic unit 62 diagnoses the presence or absence of an abnormality in the power supply equipment according to the diagnostic information generated by the diagnostic information generation unit 61. Specifically, it diagnoses the presence or absence of loosening of the bolts at the bolt fastening parts between conductors. In the diagnosis, the diagnostic unit 62 compares, as an example, the decay rate of the vibration acceleration in the diagnostic information generated by the diagnostic information generation unit 61 with a predetermined threshold value. For example, when such a decay rate is greater than or equal to the predetermined threshold value, the diagnostic unit 62 can diagnose that loosening of the bolt has occurred at the bolt fastening part and the bolt is not tightened with an appropriate tightening torque. Therefore, in this case, it is diagnosed that an abnormality has occurred in the power supply equipment. On the contrary, when such a decay rate is less than the predetermined threshold value, the diagnostic unit 62 can diagnose that no loosening of the bolt has occurred at the bolt fastening part and the bolt is tightened with an appropriate tightening torque. Therefore, in this case, it is diagnosed that no abnormality has occurred in the power supply equipment.

[0020] In such an abnormality diagnosis device 1, when diagnosing an abnormality in the power supply equipment, the vibration excitation unit 2 and the measurement unit 3 are respectively attached to predetermined locations. The attached vibration excitation unit 2 and measurement unit 3 are removed after the abnormality diagnosis of the power supply equipment is completed. That is, the vibration excitation unit 2 and the measurement unit 3 are detachably attached as appropriate.

[0021] FIG. 2 is a diagram schematically showing the configuration of the abnormality diagnosis device 1 when diagnosing an abnormality in the power supply equipment 10. As shown in FIG. 2, in the power supply equipment 10, the conductor 11 is fixed to the shelf board of the housing 12 with bolts 13a and 13b. The bolts 13a and 13b are fastened to the shelf board of the housing 12 via fixing members 14a and 14b. The fixing members 14a and 14b are insulating members such as insulators. The fixing members 14a and 14b cover the portion of the shaft part 134 of the bolts 13a and 13b that penetrates through the conductor 11. The conductor 11 is made of, for example, copper which is a good conductor of electricity, aluminum with a small specific resistance, etc., and has a flat shape extending in a predetermined direction. The predetermined direction (the direction in which the conductor 11 extends) is, for example, the horizontal direction, the vertical direction, or a direction inclined with respect to these. When the power supply equipment 10 includes a plurality of boards, it is the arrangement direction of the boards (the left - right direction in FIG. 2), etc.

[0022] In the example shown in Figure 2, two conductors 11a and 11b are arranged along a predetermined direction. These conductors 11a and 11b are fastened together by fastening members and are electrically connected. In the illustrated example, the two conductors 11a and 11b, that is, adjacent conductors 11a and 11b in the predetermined direction, are fastened together by bolts 13c and nuts 15a. That is, each conductor 11a and 11b is fixed to the shelf of the housing 12 by bolts 13a and 13b via fixing members 14a and 14b, and is also electrically connected to each other by bolts 13c. A washer 16a is interposed between the bolt 13c and the nut 15a. Bolts 13a, 13b, 13c and nuts 15a are examples of fastening members (bolt 13c is the first fastening member, and bolts 13a and 13b are the second fastening members), and the fastening members are not limited to these.

[0023] The vibration excitation unit 2 and the measurement units 3a and 3b should be positioned at or near the fixing points Pa and Pb where the conductors 11a and 11b are fixed to the housing 12 by fastening members, bolts 13a and 13b. The fixing points Pa and Pb are the respective points where the conductors 11a and 11b are fixed to the housing 12 by bolts 13a and 13b, with the bolt fastening part 20a in between. In other words, the conductors 11a and 11b have fixing points Pa and Pb fixed to the housing 12. The vicinity of the fixing points Pa and Pb is the region included within a predetermined distance from the fixing points Pa and Pb. The predetermined distance is, for example, a distance range within 10% of the distance between the fixing points Pa and Pb (distance D shown in Figure 2). In this case, the distance D between the fixing points Pa and Pb is the shortest distance between the axes of the bolts 13a and 13b in the predetermined direction in which the conductors 11a and 11b extend.

[0024] In the example shown in Figure 2, the excitation unit 2 is positioned on the bolt 13a. The measurement unit 3a is positioned on the bolt 13a, and the measurement unit 3b is positioned on the bolt 13b. In the example shown in Figure 2, the vibration characteristics of the fastening point (bolt fastening part) 20a between the conductor 11a and the conductor 11b by the bolt 13c are measured by these excitation unit 2 and measurement units 3a and 3b. The measurement unit 3a measures the vibration characteristics on the side of the bolt fastening part 2 that is being excited by the excitation unit 2 (the input side of the vibration). The measurement unit 3b measures the vibration characteristics on the opposite side of the bolt fastening part 2 from the side being excited by the excitation unit 2 (the output side of the vibration).

[0025] The vibration section 2, the measurement sections 3a and 3b, and the bolts 13a and 13b are made of magnetic material at least in the parts that are positioned relative to each other (the parts that come into contact with each other). A magnetic material is a substance that can become magnetic, in short, a substance that can be attracted to a magnet. For example, the vibration section 2 and the measurement sections 3a and 3b only need to have the parts that come into contact with the bolts 13a and 13b made of an iron-based material. Also, the bolts 13a and 13b may be made entirely of an iron-based material, or the entire bolt or the bolt head may have a surface treatment such as plating with an iron-based material.

[0026] The vibration unit 2 is attached to the bolt 13a with a magnet 17a. The measurement unit 3a is attached to the bolt 13a with a magnet 17b. The measurement unit 3b is attached to the bolt 13b with a magnet 17c. In other words, the vibration unit 2 and the measurement units 3a and 3b are positioned with magnets 17a, 17b, and 17c at fixing points Pa and Pb where the conductors 11a and 11b are fixed to the housing 12 with bolts 13a and 13b. This makes it easy to attach and detach the vibration unit 2 and the measurement units 3a and 3b to the fixing points Pa and Pb, and in other words, to the bolts 13a and 13b. The vibration unit 2 and magnet 17a, the measurement unit 3a and magnet 17b, and the measurement unit 3b and magnet 17c are pre-integrated so that they can be handled as a single unit. These can be integrated by, for example, joining with adhesive or double-sided tape, or joining with screws.

[0027] In the example shown in Figure 2, the excitation unit 2 and the measurement units 3a and 3b are attached to bolts 13a and 13b corresponding to the fixing points Pa and Pb, but they may also be attached in the vicinity of bolts 13a and 13b. The vicinity of bolts 13a and 13b is, for example, within 10% of the distance D from the bolts 13a and 13b. When attaching the excitation unit 2 and the measurement units 3a and 3b in the vicinity of bolts 13a and 13b with magnets 17a, 17b, and 17c, the following arrangement can be taken. For example, if the conductors 11a and 11b are magnetic materials such as iron, the excitation unit 2 and the measurement units 3a and 3b can be attached to the vicinity of bolts 13a and 13b of the conductors 11a and 11b via magnets 17a, 17b, and 17c. On the other hand, if the conductors 11a and 11b are non-magnetic materials such as copper or aluminum, for example, a magnetic plate can be attached near the bolts 13a and 13b of the conductors 11a and 11b, or a magnetic coating can be formed near them, making the magnet placement area (magnet mounting area) magnetic. This makes it possible to attach the vibration unit 2 and the measurement unit 3a and 3b to the bolts 13a and 13b of the conductors 11a and 11b using magnets 17a, 17b, and 17c. Also, in the example shown in Figure 2, the vibration unit 2 is attached to the bolt 13a with magnet 17a and the measurement unit 3a is attached to the bolt 13a with magnet 17b, but the vibration unit 2 and the measurement unit 3a may be attached to the bolt 13a together with a single magnet.

[0028] Furthermore, in the example shown in Figure 2, the vibration excitation unit 2 and the measurement units 3a, 3b are attached to the end face (upper surface in Figure 2) 132 of the bolt head 131 of the bolts 13a, 13b, but the attachment locations are not limited to this. For example, the vibration excitation unit 2 and the measurement units 3a, 3b may be attached to the side surface 133 of the bolt head 131 of the bolts 13a, 13b. Also, for example, if the tip 135 of the shaft portion 134 of the bolts 13a, 13b is exposed from the fixing members 14a, 14b, or if the fixing members 14a, 14b are not present, the vibration excitation unit 2 and the measurement units 3a, 3b may be attached to the shaft portion 134 or the tip 135 of the shaft portion 134.

[0029] With the vibration excitation unit 2 and measurement units 3a and 3b attached to the bolts 13a and 13b in this manner, the vibration excitation unit 2 is operated to apply vibration to the conductors 11a and 11b, and the vibration characteristics of the vibration before and after the bolt fastening portion 20a, i.e., on the input and output sides of the vibration, are measured by the measurement units 3a and 3b, respectively. Based on the measured values ​​from the measurement units 3a and 3b, the control unit 6 (diagnostic information generation unit 61 and diagnostic unit 62) diagnoses an abnormality in the power supply equipment 10, specifically whether or not the bolts 13c are loose. After the diagnosis, the vibration excitation unit 2 and measurement units 3a and 3b are removed from the bolts 13a and 13b.

[0030] The vibration generated by the excitation unit 2 travels from the bolt 13a through the conductor 11a to the bolt fastening part 20a, and then through the conductor 11b to the bolt 13b. As the vibration travels through the conductor 11a, the bolt fastening part 20a, and the conductor 11b, it gradually attenuates. The vibration characteristics of this vibration, such as acceleration, are measured by the measuring unit 3a located on the bolt 13a and the measuring unit 3b located on the bolt 13b, respectively. For example, if the bolt 13c is not fastened with the correct tightening torque at the bolt fastening part 20a, that is, if the bolt 13c is loose (abnormal condition), the pressure (contact pressure) pressing the conductors 11a and 11b together decreases. When the contact pressure decreases, the transmission of vibration from conductor 11a to conductor 11b is inhibited. As a result, the vibration acceleration measured by the measuring unit 3b in the abnormal condition is even lower than when the bolt 13c is fastened with the correct tightening torque (normal condition).

[0031] Therefore, if the difference in vibration acceleration between the measurement unit 3a and the measurement unit 3b is greater than a predetermined threshold compared to the difference in the normal state (the difference in the normal value mentioned above), it is possible to diagnose that the bolt 13c is loose. In other words, in this case, it is possible to determine that there is a possibility of an abnormality in the power supply equipment 10. Conversely, if the difference in vibration acceleration between the measurement unit 3a and the measurement unit 3b is less than or equal to a predetermined threshold compared to the difference in the normal state, in short, if it is approximately the same as the difference in the normal state, it is possible to diagnose that the bolt 13c is not loose. In other words, in this case, it is possible to determine that there is a low possibility of an abnormality in the power supply equipment 10, that is, the power supply equipment 10 is normal. Such thresholds are stored in the memory device of the control unit 6 along with the normal value and are read out as parameters when diagnosing whether or not the bolt 13c is loose. The normal value here is, for example, the measured value of vibration acceleration that shows the vibration characteristics of the conductors 11a and 11b generated by the vibration applied by the excitation unit 2 when the bolt 13c is fastened with the appropriate tightening torque in the bolt fastening part 20a.

[0032] Figure 3 shows the time transition of vibration acceleration generated by the excitation unit 20 under normal and abnormal conditions. In Figure 3, the vertical axis represents vibration acceleration, and the horizontal axis represents time. In Figure 3, the dashed line shows the time transition of vibration acceleration under normal conditions, and the solid line shows the time transition of vibration acceleration under abnormal conditions. As shown in Figure 3, the vibration input at the excitation timing indicated by arrow A1 passes through the bolt fastening part 20a as time progresses. Under abnormal conditions where the bolt 13c is loose, the vibration is attenuated as it passes through the bolt fastening part 20a including the bolt 13c, compared to the normal condition where the bolt 13c is fastened with the appropriate tightening torque, and the acceleration decreases as indicated by arrow A2. Therefore, by capturing the change in the measured value of vibration acceleration relative to the value of vibration acceleration under normal conditions (normal value), that is, by comparing the difference between the two with a threshold, the loosening of the bolt 13c can be detected.

[0033] Here, we will explain an example of overheating in a bolted connection due to loosening of a common bolt. For example, when two conductors are fastened together with a bolt, if the bolt is tightened with the correct torque, the contact resistance of the conductors will stabilize at around a few microohms. However, if the bolt loosens due to improper tightening or vibration, the contact pressure between the conductors decreases, reducing the number of contact points between the conductors, and causing heat generation due to the concentration of current. As the heat generation progresses, oxidation of the metal surface of the conductors progresses, increasing the contact resistance between them. Furthermore, when the temperature of the conductors exceeds, for example, 200°C, warping due to softening of the conductor metal begins to occur, and in this case, the contact resistance between the conductors increases even further. When the contact resistance between the conductors exceeds several hundred microohms, the current path concentrates on the bolt instead of between the conductors as intended, and the bolt may overheat and melt. For this reason, it is important to detect overheating in bolted connections.

[0034] In this embodiment, the vibration excitation unit 2 and the measurement unit 3 are positioned on bolts 13a and 13b fastened to the shelf plate of the housing 12 via fixing members 14a and 14b. For example, if the vibration excitation unit 2 and the measurement unit 3 are positioned on the outer surface of the conductor 11, which is far from such fastening points, the acceleration and amplitude of vibration at those positions tend to be large, and there is a risk that the measurement results that may be caused by the structure will be large. In this case, it becomes difficult to interpret the measured values, and the accuracy of anomaly diagnosis tends to decrease. Therefore, by positioning the vibration excitation unit 2 and the measurement unit 3 on bolts 13a and 13b, in other words, on fixing points Pa and Pb of the conductors 11a and 11b to the housing 12, as in this embodiment, the error in the measured values ​​can be minimized. This makes it possible to interpret the measured values ​​and improve the accuracy of anomaly diagnosis.

[0035] Methods for detecting overheating in bolted fastening sections include, for example, the installation of a wireless temperature sensor or an abnormal overheating detection device consisting of an odor generator and an odor detector, in which an abnormality is detected when the temperature at the installation location exceeds a predetermined value. However, these methods require the predetermined detection device to be pre-installed within the power supply equipment, which is time-consuming and inefficient, as well as requiring space to be secured for the installation of the detection device.

[0036] In contrast, according to this embodiment, the vibration excitation unit 2 and the measurement unit 3 can be easily attached to and detached from the bolts 13a and 13b using magnets 17a, 17b, and 17c. Therefore, fixing work such as joining the vibration excitation unit 2 and the measurement unit 3 with adhesive or screwing is unnecessary. Furthermore, by attaching the vibration excitation unit 2 and the measurement unit 3 to the bolts 13a and 13b or nearby, it is easier to avoid circuit breakers, transformers, branch busbars, power cables, etc., located within the power supply equipment, and to secure space for attaching the vibration excitation unit 2 and the measurement unit 3. This improves the workability when attaching the vibration excitation unit 2 and the measurement unit 3. As a result, the time required to measure vibration characteristics can be shortened, and the diagnosis of whether or not an abnormality has occurred in the power supply equipment 10 can be made more efficient.

[0037] In the first embodiment described above, the excitation unit 2 and the measurement unit 3a are configured as separate and independent components on the vibration input side. These excitation unit 2 and measurement unit 3a may be configured as a single integrated component. Hereinafter, an embodiment in which the excitation unit 2 and measurement unit 3a are integrated will be described as the second embodiment.

[0038] (Second embodiment) Figures 4 and 5 show the abnormality diagnosis device 100 according to the second embodiment. Figure 4 is a block diagram showing the schematic configuration of the abnormality diagnosis device 1 according to this embodiment. Figure 5 is a schematic diagram showing the abnormality diagnosis device 100 when diagnosing an abnormality in the power supply equipment 10 according to this embodiment. In the second embodiment, the basic configuration of the abnormality diagnosis device 100 is the same as that of the abnormality diagnosis device 1 according to the first embodiment shown in Figures 1 and 2. Therefore, in the second embodiment, the components of the abnormality diagnosis device 100 that are the same as or similar to those of the abnormality diagnosis device 1 are described using the same reference numerals as the components of the abnormality diagnosis device 1 shown in Figures 1 and 2.

[0039] As shown in Figure 4, the anomaly diagnosis device 100, like the anomaly diagnosis device 1 shown in Figure 1, comprises a measurement unit 3, a communication unit 4, an output unit 5, and a control unit 6 as its main components. In addition, the anomaly diagnosis device 100 includes a vibration measurement unit 7, which will be described later, instead of the vibration excitation unit 2. As shown in Figure 5, in the power supply equipment 10, the conductor 11 is fixed to the shelf of the housing 12 with bolts 13a, 13b, and 13d. The bolts 13a, 13b, and 13d are fastened to the shelf of the housing 12 via fixing members 14a, 14b, and 14c. The fixing members 14a, 14b, and 14c are insulating members such as insulators.

[0040] In the example shown in Figure 5, two conductors 11a and 11b, that is, adjacent conductors 11a and 11b, are electrically connected by fastening a bolt 13c and a nut 15a. Furthermore, two conductors 11b and 11c, that is, adjacent conductors 11b and 11c, are electrically connected by fastening a bolt 13e and a nut 15b. In other words, three conductors 11a, 11b, and 11c are fastened together by two bolts 13c and 13e to form a series and are electrically connected. To put it another way, each conductor 11a, 11b, and 11c is fixed to the shelf of the housing 12 by bolts 13a, 13b, and 13d, respectively, and is electrically connected to each other by fastening a bolt 13c and 13e. A washer 16a is interposed between bolt 13c and nut 15a, and a washer 16b is interposed between bolt 13e and nut 15b. Bolts 13a to 13e and nuts 15a and 15b are examples of fastening members (bolts 13c and 3e are first fastening members, and bolts 13a, 13b, and 13d are second fastening members), and the fastening members are not limited to these.

[0041] Furthermore, in the example shown in Figure 5, there are multiple (two) bolted fastening points 20a and 20b between the vibration input side and the output side. Bolted fastening point 20a is where conductors 11a and 11b are fastened with bolts 13c. Bolted fastening point 20b is where conductors 11b and 11c are fastened with bolts 13e. The abnormality diagnosis device 100 diagnoses whether there is an abnormality in these two bolted fastening points 20a and 20b, specifically whether the bolts 13c and 13e are loose.

[0042] A measuring unit 3b is positioned on the bolt 13b, which is on the vibration output side of the bolt fastening portion 20a. The measuring unit 3b measures the vibration characteristics at the bolt fastening portion 20a. A measuring unit 3c is positioned on the bolt 13d, which is on the vibration output side of the bolt fastening portion 20b. The measuring unit 3c measures the vibration characteristics at the bolt fastening portion 20b. The measuring unit 3b is attached to the bolt 13b with a magnet 17c. The measuring unit 3c is attached to the bolt 13d with a magnet 17d. In other words, the measuring units 3b and 3c are positioned with magnets 17c and 17d at fixing points Pb and Pc, where the conductors 11b and 11c are fixed to the housing 12 with bolts 13b and 13c. This makes it easy to attach and detach the measuring units 3b and 3c to the bolts 13b and 13d. The measuring unit 3b and magnet 17c, and the measuring unit 3c and magnet 17d are pre-integrated to allow for integrated handling. These can be integrated by methods such as adhesive, double-sided tape, or screws. The measuring units 3b and 3c may also be attached near the bolts 13b and 13d.

[0043] A vibration measurement unit 7 is positioned on the bolt 13a, which is on the vibration input side, flanking the bolt fastening portions 20a and 20b. The vibration measurement unit 7 is an integrated component comprising a vibrator 71 that applies vibration to the conductor 11 and a measuring instrument 72 that measures values ​​indicating the characteristics of the vibration applied by the vibrator 71. In other words, the vibration measurement unit 7 makes it possible to handle the vibrator 71 and the measuring instrument 72 as a single unit. The vibrator 71 is an element that performs the same function as the vibration unit 2 of the abnormality diagnosis device 1 according to the first embodiment. The measuring instrument 72 is an element that performs the same function as the measurement unit 3a of the abnormality diagnosis device 1 and corresponds to one of the multiple measurement units in the abnormality diagnosis device 100.

[0044] The vibration measurement unit 7 includes a magnet 73 in addition to the vibrator 71 and measuring instrument 72. The vibration measurement unit 7 is attached to the bolt 13a by the magnet 73. That is, the vibration measurement unit 7 is positioned by the magnet 73 at the fixing point Pa where the conductor 11a is fixed to the housing 12 by the bolt 13a. This makes it easy to attach and detach the vibration measurement unit 7 from the bolt 13a. The vibration measurement unit 7 may also be attached in the vicinity of the bolt 13a.

[0045] Thus, the vibrator 71 is positioned near the bolt 13a at the fixing point Pa of one of the conductors 11a, which is fastened by the bolt fastening part 20a. The measuring instrument 72 is positioned near the bolt 13a at the same fixing point Pa as the vibrator 71. The measuring units 3b and 3c are positioned near the bolts 13b and 13d at the fixing points Pb and Pc of conductors 11b and 11c, which are located on the opposite side of the bolt fastening part 20a from the conductor 11a.

[0046] Figure 6 is a schematic diagram showing a general configuration example of the vibration measurement unit 7. As shown in Figure 6, the vibration measurement unit 7 is composed of the following main elements: an exciter 71, a measuring instrument 72, a magnet 73, a stopper 74, and a housing 75. The exciter 71, measuring instrument 72, magnet 73, and stopper 74 are housed in the housing 75.

[0047] The vibrator 71 is an element that generates vibrations, for example, by a speaker mechanism, and has a speaker fixing part 71a, a speaker movable part 71b, and a diaphragm 71c. The speaker fixing part 71a is the part of the vibrator 71 that is fixed to the housing 75, in other words, the stationary part relative to the housing 75. The speaker fixing part 71a has, for example, a voice coil and a magnet (not shown) inside. The speaker movable part 71b is a movable part of the vibrator 71 and is coupled to the speaker fixing part 71a and vibrates relative to the speaker fixing part 71a. The diaphragm 71c is a plate material that works in conjunction with the speaker movable part 71b and vibrates in sync with the speaker movable part 71b. As a result, vibration can be input to the conductor 11 via the diaphragm 71c. The diaphragm 71c is flat, and one of its main surfaces (hereinafter referred to as the first surface) 71d is fixed to the speaker movable part 71b.

[0048] The measuring instrument 72 is a contact-type acceleration sensor, such as a piezoelectric element or a strain gauge, and is placed on the diaphragm 71c. In the example shown in Figure 6, the measuring instrument 72 is fixed to the first surface 71d of the diaphragm 71c. As a result, the measuring instrument 72 measures a value that indicates the characteristics of the vibration generated in the diaphragm 71c, in other words, the characteristics of the vibration that the exciter 71 imparts to the conductor 11.

[0049] The magnet 73 has magnetic force that allows the vibration measurement unit 7 to be attached, for example, to a bolt 13a, and is fixed to the second surface 71e of the diaphragm 71c. The second surface 71e is the surface of the diaphragm 71c that faces away from the first surface 71d and is the surface that faces the mounting side of the vibration measurement unit 7 to the bolt 13a. When fixed to the second surface 71e of the diaphragm 71c, a part of the magnet 73 is exposed from the housing 75 and can be attached to and detached from the end face 132 of the bolt head 131 of the bolt 13a.

[0050] The stopper 74 restricts the movement of the diaphragm 71c when the vibration measurement unit 7 is removed from the bolt 13a after the abnormality diagnosis device 100 has finished diagnosing whether there is an abnormality in the bolt fastening parts 20a and 20b, specifically whether the bolts 13c and 13e are loose. When the vibration measurement unit 7 is removed from the bolt 13a, the housing 75 is gripped and the entire vibration measurement unit 7 is pulled up. In this case, the speaker fixing part 71a is fixed to the housing 75 and is therefore pulled up together with the housing 75. On the other hand, the diaphragm 71c is attached to the bolt 13a by the magnet 73 and therefore tries to maintain its position. As a result, a force is generated by the magnet 73 that tries to separate the diaphragm 71c and the speaker movable part 71b, which may damage the diaphragm 71c and the speaker movable part 71b.

[0051] When the housing 75 is gripped and the entire vibration measurement unit 7 is pulled up relative to the bolt 13a, the stopper 74 shifts upward along with the housing 75 and comes into contact with the diaphragm 71c. As a result, the diaphragm 71c is also pulled up along with the speaker fixing part 71a and the housing 75. Consequently, the generation of a force that would separate the diaphragm 71c and the speaker movable part 71b, which are fixed together, is suppressed. Therefore, by providing the stopper 74, damage to the diaphragm 71c and the speaker movable part 71b can be suppressed and they can be protected.

[0052] By integrating the vibrator 71, measuring instrument 72, and magnet 73 in this way to constitute the vibration measurement unit 7, the vibrator 71 and measuring instrument 72 can be attached together to the bolt 13a or its vicinity using the magnet 73. Therefore, the workability in this process can be further improved.

[0053] It is also possible to omit the housing 75 and stopper 74 in the vibration measurement unit 7 shown in Figure 6, as shown in Figure 7, which is a modified example of the vibration measurement unit 7. The vibration measurement unit 7a is configured similarly to the vibration measurement unit 7, and includes an exciter 71, measuring instrument 72, and magnet 73, in addition to the housing 75 and stopper 74.

[0054] As described above, in the example shown in Figure 5, two bolted fastening sections 20a and 20b are included between the input and output sides of the vibration. With the vibration measurement unit 7 and measurement sections 3b and 3c installed as described above, the exciter 71 of the vibration measurement unit 7 is operated to generate vibration, and the vibration characteristics of the vibration before and after the bolted fastening sections 20a and 20b, i.e., on the input and output sides of the vibration, are measured by the measuring instrument 72 and measurement sections 3b and 3c, respectively.

[0055] The vibration generated by the vibrator 71 travels from bolt 13a through conductor 11a to bolt fastening part 20a, then through conductor 11b to bolt 13b. Furthermore, this vibration travels from bolt 13b through conductor 11b to bolt fastening part 20b, then through conductor 11c to bolt 13d. This vibration gradually attenuates as it travels through conductor 11a, bolt fastening part 20a, conductor 11b, bolt fastening part 20b, and conductor 11c. The vibration characteristics of this vibration, such as acceleration, are measured by measuring instrument 72 located on bolt 13a, measuring unit 3b located on bolt 13b, and measuring unit 3c located on bolt 13d, respectively. Specifically, measuring unit 3b measures the fastening state (in other words, the loosening state) of bolt 13c at bolt fastening part 20a. In contrast, the measurement unit 3c measures not only the fastening state of bolt 13c in bolt fastening section 20a, but also the fastening state (in other words, the loosening state) of bolt 13e in bolt fastening section 20b.

[0056] Therefore, for example, if the bolts 13c and 13e in the bolt fastening sections 20a and 20b are both fastened with the appropriate tightening torque (normal condition), the difference in vibration acceleration between the measuring instrument 72 and the measuring sections 3b and 3c will be approximately the same as the difference under normal conditions.

[0057] However, for example, in the bolt fastening section 20a, if the bolt 13c is not fastened with the correct tightening torque, that is, if the bolt 13c is loose (abnormal condition), the difference in vibration acceleration between the measuring instrument 72 and the measuring unit 3b will be greater than a predetermined threshold compared to the difference under normal conditions. Also, in this case, if the bolt 13e is fastened with the correct tightening torque in the bolt fastening section 20b, that is, if the bolt 13e is not loose (normal condition), the difference in vibration acceleration between the measuring instrument 72 and the measuring unit 3c will be greater than a predetermined threshold compared to the difference under normal conditions.

[0058] In contrast, for example, if the bolt 13c is fastened with the correct tightening torque at the bolt fastening portion 20a (normal state), but the bolt 13e is not fastened with the correct tightening torque at the bolt fastening portion 20b, that is, the bolt 13e is loose (abnormal state), then only the difference in vibration acceleration between the measuring instrument 72 and the measuring unit 3c will be greater than a predetermined threshold compared to the difference in the normal state.

[0059] Based on the above, by appropriately positioning the measuring units 3b and 3c corresponding to each bolt fastening section 20a and 20b, it becomes possible to identify which bolts 13c and 13e of these bolt fastening sections 20a and 20b are loose. In other words, even if there are multiple bolt fastening sections, by sequentially shifting the measuring units, it becomes possible to identify which bolts of which bolt fastening section are loose.

[0060] In this configuration, the vibration measurement unit 7 (vibrator 71, measuring instrument 72) and the measuring units 3b and 3c can be easily attached to and detached from the bolts 13a, 13b, and 13d using magnets 73, 17c, and 17d. This improves the workability when attaching the vibration measurement unit 7 (vibrator 71, measuring instrument 72) and the measuring units 3b and 3c to the bolts 13a, 13b, and 13d or their vicinity. As a result, similar to the first embodiment, the time required to measure vibration characteristics can be reduced, and the efficiency of diagnosing whether or not an abnormality has occurred in the power supply equipment 10 can be improved.

[0061] Generally, power supply equipment designs vary depending on constraints such as the type of equipment connected, power capacity, and operating conditions, resulting in a wide range of conductor configurations and structures. Therefore, it is necessary to pre-measure and obtain the vibration characteristics under normal conditions for each power supply equipment subject to abnormality diagnosis. Power supply equipment is usually composed of multiple panels, and there are multiple bolt fastening points (bolt fastening points) for fixing conductors to the panels, connecting between panels, and connecting to various equipment. In order to confirm and understand the fastening status of these bolts, it is necessary to measure the fastening status of the bolts at each of the multiple bolt fastening points. For this reason, the more bolt fastening points, and thus the more points where vibration is measured, the longer the measurement time tends to be.

[0062] In this respect, according to this embodiment, the vibration measurement unit 7 (vibrator 71, measuring instrument 72) and measuring units 3b, 3c can be easily attached to and detached from bolts 13a, 13b, 13d using magnets 73, 17c, 17d. That is, even if there are multiple bolt fastening points, the vibration measurement unit 7 and measuring units 3b, 3c can be easily attached, making it easy to identify the bolt fastening point where an abnormality is occurring, i.e., the bolt that has become loose. As a result, the time required for diagnosing abnormalities in power supply equipment can be shortened.

[0063] Although several embodiments of the present invention have been described above, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0064] 1,100…Anomaly diagnosis device, 2…Excitation unit, 3,3a,3b,3c…Measurement unit, 4…Communication unit, 5…Output unit, 6…Control unit, 7,7a…Excitation measurement unit, 10…Power supply equipment, 11,11a,11b,11c…Conductor, 12…Housing, 13a,13b,13c,13d,13e…Bolts, 14a,14b,14c…Fixing members, 15a,15b…Nuts, 16a,16b…Washers, 17a,17b,17c,17d…Magnets, 20a,20b… Bolt fastening section, 61...Diagnostic information generation section, 62...Diagnostic section, 71...Vibrator, 71a...Speaker fixing section, 71b...Speaker movable section, 71c...Diaphragm, 72...Measuring instrument, 73...Magnet, 73a...Exposed part, 74...Stopper, 75...Housing, 131...Bolt head, 132...End face of bolt head, 133...Side of bolt head, 134...Shaft of bolt, 135...Tip of bolt shaft, D...Distance between fixing points, Pa, Pb, Pc...Fixing points.

Claims

1. An abnormality diagnosis device for diagnosing abnormalities in power supply equipment comprising a housing and a conductor fixed to the housing at predetermined fixed locations for supplying current to a load, An excitation unit that applies vibration to the conductor, The system includes a measuring unit that measures a value indicating the characteristics of the vibration applied to the conductor by the excitation unit, The power supply equipment is configured such that each of the plurality of conductors has a fixing point, and adjacent conductors are electrically connected at fastening points fastened with a first fastening member. Each of the plurality of conductors is fastened to the housing at the fixing point by a second fastening member. The vibration excitation part is positioned near the second fastening member that fastens one of the conductors fastened at the fastening point, The measurement units are arranged in multiple locations near the second fastening member or the second fastening member, one of the multiple measurement units is arranged near the same second fastening member or the second fastening member as the vibration unit, and the other measurement units are arranged at multiple different locations near the second fastening member or the second fastening member that fastens the conductor located on the opposite side of the fastening point from the one conductor. The vibration excitation unit and the second fastening member, which is the same as the vibration excitation unit, or the measurement unit, which is positioned on the second fastening member, are configured as a single integrated component. Anomaly detection device.

2. The vibration excitation unit and the measurement unit, and the fixed location or the vicinity of the fixed location, are arranged such that their relative positions are made of magnetic material. The vibration excitation unit and the measurement unit are detachably arranged at or near the fixed location via a magnet. An abnormality diagnosis device according to claim 1.

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